Manually-operated food slicers have been used in restaurants and food markets for many years to slice food products with the result of uneven product thickness, operating inconvenience and labor inefficiency, especially for the daily demand of considerable quantities.
A manually-operated food slicer is basically equipped with a motor-driven inclined (usually about 45 degree to vertical) circular knife, an inclined (same inclined angle as the circular knife) food-table and table-frame assembly, a slice-gauge adjusting mechanism, and a reciprocally movable food-carriage. The food-table and table-frame assembly is fastened on a mounting block that connects to the slice-gauge adjusting mechanism by a precision gear and guide system to adjust the food-table to a certain distance related to the circular knife for a desire food slice thickness. The food-carriage is mounted for lateral movement in a linear path to feed the food product, which is loaded on the food-table, into contact with the circular knife to produce food slices. The food-carriage usually includes an automatic down-feeding press-arm to keep the product loaded against the food-table while the food-carriage moves the product along its path to cut the slices to a consistent thickness after the operator sets the desired thickness on the machine's slice-gauge adjuster. But often, the cutting thickness of a slicer cannot be kept consistent as desired because of the inconstant sliding friction created by the loaded food, which is relatively soft and travels back and forth on the food-table controlled by the food-carriage that is pushed and pulled by the operator during the cutting process. Unlike two ridge bodies, the slide movement between a soft but dense body, as meat products, and a hard body, as the metal food-table, not only generates greater friction but also creates uneven and inconstant friction, unless the driving force is uniformly spread on the soft body during the action. Although the current food-tables have shallow lateral slots for the purpose of reducing some of the slide friction in the cutting process, they can only help to a certain degree, especially when there is uneven and inconstant friction between the food and the food-table, since the driving force acting on the food through the food-carriage is not uniformly spread. This uneven and inconstant slide friction between the food and food-table gradually changes the movement and position of the loaded food in the cutting process and causes the food slicer to produce slices with uneven thickness, even a single slice may vary in thickness. This uneven and inconstant sliding friction becomes more noticeable when the loaded food is heavier and wetter, which causes the loaded food gradually being inclined on the food table, regardless the limited restriction of the food-carriage, to eventually jam the food in the gap between the food-table and the food-carriage. In this situation, more force must be supplied on the food-carriage by the operator to keep the food moving, and frequently, more time is wasted by the operator to reset the slice gauge to the desired product thickness, but often the uneven and inconstant friction prohibits the operator from controlling the thickness of the slices.
U.S. Pat. No. 2,768,666 issued in the name of Garapolo and assigned to Wilson & Co. discloses an automatic slice thickness control method by adding a hydraulic system with the relative mechanisms, including cylinder, valve, link-rod, etc., to the food-carriage to control the feed speed of a bacon slicing machine, which in turn controls the slice thickness. U.S. Pat. No. 3,938,602 to Sly et al. illustrates a scale method to control the slice product portion weight, but not to control the thickness of the slice products. U.S. Pat. No. 4,813,316 issued in the name of Johnson and assigned to Hobart Corporation illustrates a method by using an electric motor to drive the food-carriage to control the slice products. None of these methods or devices is capable of changing the uneven and inconstant slide friction of the food slicer, which is the main cause of the product slice quality and operating inconvenience and inefficiency.
Accordingly, the primary object of the present invention is to provide a new lubrication free plain bearing feeding mechanism for the food slicer, especially for the manually-operated food slicer to solve the large and uneven slide friction problems while significantly improve the quality and the function of the food-slicing machine.
Another object of the present invention is to provide a new apparatus that will reduce the food sliding friction and food inclined situation in the cutting process for the automatic power driven carriage food slicer as well as reducing the driving force, yet producing high quality food slice products.
The further object of the present invention is to provide a new apparatus that will reduce the waste of the food product, which is loaded on the slice machine, as friction reduction improves gauge reliability such that the necessity of a slice thickness-testing sample is eliminated.